An indicator light is often mounted in an electric apparatus such as an electrical connector to indicate an operating state of the electric apparatus. For example, a plurality of light emitting devices such as light emitting diodes (LEDs) may be mounted inside an electric apparatus, and a plurality of light transmitting tubes are mounted so that an input end of each light transmitting tube faces one light emitting device, and an output end thereof extends through a through hole in a panel at the front of the electric apparatus.
In this electric apparatus, a lighting state, such as lighting or dimming, or changing in lighting color, of each light emitting device may represent an operating state of some or several electrical devices in the electric apparatus. Light produced by each light emitting device is transmitted to the front of the panel through the corresponding light transmitting tube, thereby an operator can determine the operating state of the electrical device by observing a lighting condition at the output end of the light transmitting tube from the front of the panel.
FIG. 1 is a perspective view of a conventional connector assembly 206 where an electrical connection device or optical fiber connection device (not shown) is mounted within a housing 201. The housing 201 has a light transmitting tube 202 made of a transparent light guide material, such as polycarbonate (PC) material, that transmits light from a LED signal lamp 204 positioned at a rear or middle position on a circuit board 203(for example, a PCB (print circuit board)) to the front of the connector. A user is then able to observe signal light from a light outlet in front of the light transmitting tube 202. The signal light represents an operating state of the connector.
The light transmitting tube 202 is positioned above the connector housing 201, and the signal lamp 204 is positioned behind the connector. When the connector has a double-layer housing, the light transmitting tube 202 is positioned within an interlayer, and the signal lamp is positioned behind the connector.
In addition to the light transmitting tube 202, the connector assembly 206 often includes a heat sink and clamps for fixing the heat sink. Airflow moving towards the heat sink of the connector may be partially disrupted by the light transmitting tube provided on the housing 201, resulting in a reduction in heat transfer efficiency of the heat sink. Further, airflow interference conditions may also be produced by a main body of light transmitting tube 202 and the clamps or other structures. In order to avoid these interference conditions, the light transmitting tube 202 is often formed with a plurality of curved parts that permit the airflow to move relatively undisturbed. However, such curves result a certain degree of light loss, thereby finally resulting in a reduction in light intensity at the light outlet. Such reduction in light intensity can adversely affect determination of the operating state of connector.
There is a need for an electrical connector assembly with visual operating indicators that do not disturb airflow to the heat sinks, and do not result in a reduction in light intensity at the light outlet.